filestore-hpa.yml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: custom-metrics-filestore-exporter
spec:
  replicas: 1
  selector:
    matchLabels:
      custom: metrics
  template:
    metadata:
      labels:
        custom: metrics
    spec:
      hostNetwork: true
      containers:
        - name: filestore-metrics-exporter
          image: gcr.io/hpa-filestore/amonsoftware/filestore-metrics:0.0.1
          imagePullPolicy: Always
          volumeMounts:
#            The metrics app will count the files from this path, do not change it
            - mountPath: /mnt/fileserver
              name: fileserver-pvc
          ports:
            - name: http-metrics
              containerPort: 9309
          readinessProbe:
            httpGet:
              path: /
              port: 9309
            initialDelaySeconds: 5
            timeoutSeconds: 5
        - name: prometheus-to-sd
          image: gcr.io/google-containers/prometheus-to-sd:v0.4.2
          ports:
            - name: profiler
              containerPort: 6060
          command:
            - /monitor
            - --stackdriver-prefix=custom.googleapis.com
#           Configure here the REST API
            - --source=filestore-exporter:http://localhost:9309/share_name/[FILESERVER]/
            - --pod-id=$(POD_NAME)
            - --namespace-id=$(POD_NAMESPACE)
          env:
            - name: POD_NAME
              valueFrom:
                fieldRef:
                  fieldPath: metadata.name
            - name: POD_NAMESPACE
              valueFrom:
                fieldRef:
                  fieldPath: metadata.namespace
      volumes:
        - name: fileserver-pvc
          persistentVolumeClaim:
            claimName: fileserver-claim
            readOnly: true
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: fileserver
spec:
  capacity:
    storage: [STORAGE]
  accessModes:
    - ReadOnlyMany
  nfs:
    path: /[FILESHARE]
    server: [IP_ADDRESS]
---
apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: fileserver-claim
spec:
  accessModes:
    - ReadOnlyMany
  storageClassName: ""
  resources:
    requests:
      storage: [STORAGE]
---
apiVersion: autoscaling/v2beta1
kind: HorizontalPodAutoscaler
metadata:
  name: storage-hpa
spec:
  minReplicas: 1
#  It will not scale more than this number even if there are more files
  maxReplicas: 5
  metrics:
    - external:
        metricName: custom.googleapis.com|filestore-exporter|files_count
        metricSelector:
          matchLabels:
#            This must match with the name from the metric exporter app URL
            metric.labels.share_name: [FILESERVER]
#            One file = one pod
        targetAverageValue: "1"
      type: External
  scaleTargetRef:
    apiVersion: apps/v1
    kind: Deployment
    name: [DEPLOYMENT]